Curtis 1238SE - Interfacing the Throttle and Brake Commands

10 — VEHICLE CONTROL LANGUAGE (VCL)
pg. 103
Return to TOC Curtis 1232E/34E/36E/38E & 1232SE/34SE/36SE/38SE Manual, os 31 – May 2017
e 0–100% position of the potentiometer is represented by a value from 0–32767 in VCL, and is
set up through the VCL Setup_Pot() function. It is important to use the correct setup (ONE_WIRE,
TWO_WIRE, or THREE_WIRE) since the input is automatically re-scaled for 0–100% based on the
wiring used; for example, the voltage at the Pot Low pin is automatically subtracted and re-scaled
on a THREE_WIRE pot.
Another eect of setting the rottle Type = 5 is that the signal chain for the throttle now gets its
input from a dierent source. e input to the throttle chain is now a VCL variable called VCL_
rottle instead of the throttle pot. Similarly, Brake Type = 5 means the brake signal chain will get
its input from a VCL variable called VCL_Brake rather than from the brake pot. e VCL_rottle
and VCL_Brake variables will need to be controlled in the VCL program.
One of the unique features of the potentiometer inputs (as opposed to the analog inputs) is that
they have automatic pot fault detection functions running in the motor controller OS. e VCL
programmer has access to the pot detection functions with the Setup_Pot_Faults() function. With
this function, VCL can re-set the high and low thresholds at which a fault occurs. is function
also forces the pot value to a denable level if a fault occurs. Note that the Setup_Pot_Faults()
function will work for all throttle Types (1–5). See page 123 for more detail on this function, and
Interfacing the rottle and Brake Commands (below) for further information on both the
rottle and Brake processing..
Analog Inputs
ese controllers have two generic analog inputs (pins 24 and 8). ese are shared as switch inputs
1 and 2 (Sw_1, Sw_2). e values of the analog inputs are automatically placed in VCL variables
Analog1_Input and Analog2_Input every 1 millisecond. Scaling is 0–10V = 0–1023.
User2 = Analog2_Input
will ll the User2 RAM variable with the value of the voltage at pin 8.
The filtered values of the analog inputs are also available and are automatically placed in VCL
variables Analog1_Filtered and Analog2_Filtered. Scaling is 0–10V = 0–1023. e default lter value
is 328 (10 Hz) and can be changed in VCL by changing the Analog1_Filter and Analog2_Filter values.
Scaling is 0–999 Hz = 0–32767.
Analog Output
e 1234E/36E/38E and 1234SE/36SE/38SE controllers have one analog output (pin30); the 1232E/
SE has no analog output. is output is a special driver output. e switching stage is ltered to
provide a smooth average voltage, instead of the actual PWM waveform seen on Drivers 1–5.
However, AnalogOut uses the same VCL functions Put_PWM() and Automate_PWM() used by
these other drivers. e scaling is 0–10 V = 0–32767.
Put_PWM(PWM6,6553)
will generate 2.0 volts at the analog output. VCL can monitor this output using the variable Analog_
Output.
INTERFACING THE THROTTLE AND BRAKE COMMANDS
VCL can interface and modify the throttle and brake signals at several points, from the potentiometer
to the nal motor controller command. VCL can be used to create a completely unique command,
adjust parameters to provide MultiMode, or modify the throttle command based on steering angle,
height, etc.